DroidRooter.A is a binary exploit that is used to gain root privilege on an Android device.
Based on the settings of your F-Secure security product, it will either move the file to the quarantine where it cannot spread or cause harm, or remove it.
A False Positive is when a file is incorrectly detected as harmful, usually because its code or behavior resembles known harmful programs. A False Positive will usually be fixed in a subsequent database update without any action needed on your part. If you wish, you may also:
Check for the latest database updates
First check if your F-Secure security program is using the latest detection database updates, then try scanning the file again.
Submit a sample
After checking, if you still believe the file is incorrectly detected, you can submit a sample of it for re-analysis.
NOTE If the file was moved to quarantine, you need to collect the file from quarantine before you can submit it.
Exclude a file from further scanning
If you are certain that the file is safe and want to continue using it, you can exclude it from further scanning by the F-Secure security product.
Note You need administrative rights to change the settings.
DroidRooter.A and DroidRooter.B are the 'exploid' and 'rageagainstthecage' ELF binary exploits used by Trojan:Android/DroidDream.A to gain root privilege.
It should be noted that despite listing Linux as platform in the detection name, both programs are binary Android ELF files. And, under certain circumstances, they may be considered as hack-tools that users may deliberately run to 'jailbreak' their device.